A testing process is a procedure to test electrical performance of a product after integrated circuits (ICs) are packaged. The process is to ensure the integrity of performance of the manufactured IC products and classify the tested products according to their electrical performance which can be further used as credentials to sort out the IC products into different grades. In addition, the testing process is also used to inspect appearance of the products.
The aim of electrical performance test is to ensure normal operation of final products by testing various electrical parameters of the products.
Traditional tests, such as Kelvin test, use two contact points on a same terminal to be tested. Double ejector pins or double connecting fingers are placed side by side in parallel with each other. However, there are certain drawbacks as follows.
First, the fabrication precision is low. With continuous decrease of the size of semiconductor products, the size of terminal to be tested and the distance between different terminals to be tested are also getting smaller. Following this trend, limitation of traditional methods with double parallel ejector pins or connecting fingers placed side by side having a fine-pitch arrangement becomes more evident. Precision requirements become higher and higher and some of them may not even possibly meet the precision requirements.
Second, structural strength is weak. As ejector pins or connecting fingers become thinner and thinner to realize double-contact tests within a limited space of terminals to be tested, the mechanical structural strength also becomes weaker and weaker.
Third, service lifetime is short. Traditional ejector pins or connecting fingers may be easily worn and torn, especially in the case that the precision requirement gets higher while the mechanical strength becomes relatively weaker, the degree of abrasion is more significant, and thus the service lifetime of testing fixture is reduced.
Fourth, precision of test or measurement resolution is low. As ejector pins or connecting fingers become thinner and thinner to meet the development requirement for slim and light semiconductor components, their resistance also becomes larger, thus during high current test, a large voltage drop may be induced and it further affects accuracy of test data. Moreover, double parallel ejector pins or connecting fingers may easily induce a measurement error in the test data due to their displacement deviation. In addition, traditional double parallel ejector pins use a method of two back-to slope contacts to reduce the distance between the two pins. The contact head may be pushed to rotate off from the terminal to be tested due to a twisting force caused by stretching or compressing the spring in the structure of the pin, and thus affect the precision of test.
When terminal to be tested has a spherical shape, performing tests on the electrical properties may not be possible using traditional double parallel ejector pins or connecting fingers.
The disclosed testing probe and semiconductor testing fixture, and their fabrication methods are directed to solve one or more problems set forth above and other problems in the art.